revert back to six version 1.10 to avoid errors in gsutil
revert back to six version 1.10 to avoid errors in gsutil

macarthur-lab/seqr,ssadedin/seqr,ssadedin/seqr,ssadedin/seqr,macarthur-lab/xbrowse,ssadedin/seqr,macarthur-lab/seqr,macarthur-lab/seqr,ssadedin/seqr,macarthur-lab/xbrowse,macarthur-lab/seqr,macarthur-lab/xbrowse,macarthur-lab/xbrowse,macarthur-lab/xbrowse,macarthur-lab/xbrowse,macarthur-lab/seqr